[clang] [Clang] Diagnose require_explicit_initialization for C tentative definitions (PR #234210)

[Pathri Vidya Praveen via cfe-commits]

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@@ -0,0 +1,37 @@
+// RUN: %clang_cc1 -std=c17 -fsyntax-only -Wuninitialized-explicit-init -verify %s
+// RUN: %clang_cc1 -std=c23 -fsyntax-only -Wuninitialized-explicit-init -verify %s
+
+struct ops {
+    int (*show)(void) __attribute__((require_explicit_initialization)); // #SHOW
+    int flags;
+};
+
+struct plain {
+    int a;
+};
+
+struct plain no_attribute; // no warning: no field requires explicit initialization
+
+struct ops never_completed; // expected-warning {{field in 'ops' requires explicit initialization but is not explicitly initialized}} expected-note@#SHOW {{'show' declared here}}
+static struct ops never_completed_static; // expected-warning {{field in 'ops' requires explicit initialization but is not explicitly initialized}} expected-note@#SHOW {{'show' declared here}}
+
+struct ops repeated;
+struct ops repeated; // expected-warning {{field in 'ops' requires explicit initialization but is not explicitly initialized}} expected-note@#SHOW {{'show' declared here}}
+
+struct ops completed_later;
+struct ops completed_later = { .flags=1}; // expected-warning {{field 'show' requires explicit initialization but is not explicitly initialized}} expected-note@#SHOW {{'show' declared here}}
+
+struct ops completed_ok;
+struct ops completed_ok = { .show=0};
+
+extern struct ops ext;
+
+struct late g_late; // expected-warning {{field in 'late' requires explicit initialization but is not explicitly initialized}} expected-note@#LATE_X {{'x' declared here}}
+struct late {
+    int x __attribute__((require_explicit_initialization)); // #LATE_X
+};
+
+void f(void){
+    static struct ops local_static; // expected-warning {{field in 'ops' requires explicit initialization but is not explicitly initialized}} expected-note@#SHOW {{'show' declared here}}
+    (void)&local_static;
+}
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PathriVidyaPraveen wrote:

Done, thanks!

https://github.com/llvm/llvm-project/pull/234210